Biomaterial Database

Renin activity in dog brain: enzymological similarity to cathepsin D. 1976

R P Day, and I A Reid

The distribution and biochemical properties of the renin activity present in the dog brain were compared with those of the lysosomal enzyme cathepsin D. Renin and cathepsin activity were present in all brain regions studied, in association with high angiotensinase activity. Brain renin activity was partially purified by ammonium sulfate fractionation and Sephadex gel filtration, resulting in the removal of angiotensinase activity. The specific brain renin activity increased approximately one hundred times during this procedure; cathepsin D activity accompanied the brain renin activity throughout the purification and showed a similar increase in specific activity. The renin and cathepsin activity in the partially purified preparation behaved identically during isoelectric focusing. The partially purified renin and cathepsin activity exhibited saturation kinetics with their respective substrates and were without activity above pH 6.0. Both enzyme activities were irreversibly inhibited by the pepsin inhibitor pepstatin, in nanomolar concentrations. These data, in conjunction with the literature concerning brain cathepsin, suggest that the renin activity in brain is due to cathepsin D, and that this renin activity exhibited by cathepsin D may be of limited significance under physiological conditions.

UI	MeSH Term	Description	Entries
D007525	Isoelectric Focusing	Electrophoresis in which a pH gradient is established in a gel medium and proteins migrate until they reach the site (or focus) at which the pH is equal to their isoelectric point.	Electrofocusing,Focusing, Isoelectric
D010450	Endopeptidases	A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.	Endopeptidase,Peptide Peptidohydrolases
D012083	Renin	A highly specific (Leu-Leu) endopeptidase that generates ANGIOTENSIN I from its precursor ANGIOTENSINOGEN, leading to a cascade of reactions which elevate BLOOD PRESSURE and increase sodium retention by the kidney in the RENIN-ANGIOTENSIN SYSTEM. The enzyme was formerly listed as EC 3.4.99.19.	Angiotensin-Forming Enzyme,Angiotensinogenase,Big Renin,Cryorenin,Inactive Renin,Pre-Prorenin,Preprorenin,Prorenin,Angiotensin Forming Enzyme,Pre Prorenin,Renin, Big,Renin, Inactive
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D002403	Cathepsins	A group of lysosomal proteinases or endopeptidases found in aqueous extracts of a variety of animal tissues. They function optimally within an acidic pH range. The cathepsins occur as a variety of enzyme subtypes including SERINE PROTEASES; ASPARTIC PROTEINASES; and CYSTEINE PROTEASES.	Cathepsin
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia